Identifying important life stages for monitoring and assessing risks from exposures to environmental contaminants: Results of a World Health Organization review

• Published in: Regulatory toxicology and pharmacology Vol. 69; no. 1; pp. 113 - 124
• Main Authors: Cohen Hubal, Elaine A., de Wet, Thea, Du Toit, Lilo, Firestone, Michael P., Ruchirawat, Mathuros, van Engelen, Jacqueline, Vickers, Carolyn
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Inc 01.06.2014; Elsevier
• Subjects: Animals; Childhood life stages; Cultural and geographic modifying factors; Developmental changes in children; Environmental Exposure - adverse effects; Environmental Monitoring - methods; Environmental Pollutants - chemistry; Environmental Pollution - adverse effects; Exposure assessment; Exposure factors; Exposure to environmental contaminants; Harmonized early life age groups; Humans; Risk assessment; Risk Assessment - methods; United States; United States Environmental Protection Agency; Windows of exposure; Windows of susceptibility; World Health Organization; United States; Exposure factors; Exposure to environmental contaminants; Risk assessment; Cultural and geographic modifying factors; Developmental changes in children; Childhood life stages; Windows of exposure; Exposure assessment; Harmonized early life age groups; Windows of susceptibility
• ISSN: 0273-2300; 1096-0295
• DOI: 10.1016/j.yrtph.2013.09.008

•We propose a harmonized set of age bins for assessing risks from chemical exposure.•The set of early life age groups will facilitate consistency with recent guidance.•The age bins allow results from longitudinal birth cohort studies to be combined.•Region-specific exposure factors and monitoring data are needed to apply the bins. In this paper, we summarize exposure-related issues to consider in determining the most appropriate age ranges and life stages for risk assessment. We then propose a harmonized set of age bins for monitoring and assessing risks from exposures to chemicals for global use. The focus is on preconception through adolescence, though the approach should be applicable to additional life stages. A two-tiered set of early life age groups is recommended. The first tier involves the adoption of guidance similar to the childhood age groups recommended by the U.S. Environmental Protection Agency, whereas the second tier consolidates some of those age groups to reduce the burden of developing age-specific exposure factors for different regions. While there is no single “correct” means of choosing a common set of age groups to use internationally in assessing early life exposure and risk, use of a set of defined age groups is recommended to facilitate comparisons of potential exposures and risks around the globe, the collection of data and analyses of aggregate exposure and cumulative risk. Application of these age groups for robust assessment of exposure and risk for specific populations will require region-specific exposure factors as well as local environmental monitoring data.